WASTE dumped in a 1930s landfill site appears to have been the source of a poisonous substance which contaminated a North-East beck.

The Northern Echo revealed last month that Hartburn Beck, near Eaglescliffe, Stockton, had been sealed off after being contaminated with chromium salts.

Now the Environment Agency has revealed that the toxic substance could have been lying in the area for decades.

The beck has been made safe but internet rumours about underground toxic lakes abandoned by defunct companies have proven to have no foundation. The agency also quashed the rumour that nearby chemical company, Elementis, were responsible.

Instead the Environment Agency revealed the chromium pollution came from a former landfill waste site in what used to be called Whitham Hall Quarry in Eaglescliffe.

The chromium salts had entered a tributary leading to the beck after getting into a pipe just off Durham Lane.

The Environment Agency spokesman said: “The quarry was used as a household and commercial landfill site from 1938, and waste deposited there included chromium waste, which was at the time not considered hazardous.

"There were also fewer regulations in force back then to control how landfill sites were sealed off when no longer in use.

"In February this year, contaminated groundwater from the site entered surface water drains at the site, and from there it was discharged into the watercourse.”

The Environment Agency blocked the source of pollution and Northumbrian Water flushed the water course clean.

Stockton Borough Council and Northumbrian Water all helped contain the problem and Elementis provided site facilities to store the polluted water.

Options for longer-term control of the problem are being explored.